Carburetor



Sept. 17, 1929. J JUHASZ 1,728,415

CARBURETOR Filed May 14, 1925 4 Sheets-Sheet 1 IN VEN TOR A TTORNE Y Sept. 17, 1929. JUHASZ 1,728,415

CARBURETOR Filed May 14, 1923 4 Sheets-Sheet 3 IN V EN TOR A TTORNE Y J. JUHASZ Sept. 17, 1929.

IN VEN TOR WTTORNZY Patented Sept. 17, 1929 UNITED STATES PATENT OFFICE.

JOHN J'UHASZ, OF NEW YORK, N. Y., ASSIGNOR T JUHASZ CARBURETER CORPORA- TION, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK CARBURETOR Application filed May 14,

The present invention relates to improvements in carburetors, and more particularly to multi-nozzle carburetors of the type wherein each nozzle is disposed within an individual carbureting chamber, all chambers communicating with a single carburetor outlet, the communications being controlled lay a throttle common to all of said chamers.

The main object of the invention is to provide a carburetor which is adapted to furnish a proper fuel mixture under all conditions of operation of the engine without readjustment of the carburetor parts.

Another object of the invention is to pro duce a carburetor of the type mentioned which requires no further attention than the manipulation of its throttle.

A further object of the invention is to so construct the several nozzles of the carburetor that they produce a proper mixture at low speeds just as well as at higher speeds.

A still further object of the invention is to provide a carburetor wherein the several nozzles co-operate in a manner that the resultant mixture issuing from the nozzles is properly diluted as the throttle is gradually opened, each nozzle being provided with air bleed or compensating holes. the holes in each nozzle being disposed in different levers than in the others.

A still further object of the invention is to provide a device of this character which is efficient in operation, simple in construction and capable of manufacture on a commercial scale, or in other words one which is not so diflicult to make as to be beyond the reason able cost of such a contrivance.

One of the many possible embodiments of the invention is illustrated in the accompanying drawings, in which Figure 1 is a central vertical section taken through a carburetor, partly in elevation, constructedin accordance with the present invention; Fig. 2 is a section taken on line 22 of Fig. 1; Fig. 3 is a top elevation of the carburetor; Fig. 4 is a section taken on line k4 of Fig. l, the throttle being removed; Fi 5 is a section similar to the one shown in. fig. 1 of a portion of the flea-ice with the 1923. Serial No. 638,947.

elements in other positions; Fig. 6 is a top elevation of the throttle; Fig. 7 is a bottom plan view thereof; Fig. 8 is a section taken on line 88 of Fig. 6; Fig. 9 is a section taken on line 9-9 of Fig. 6; and Fig. 10 is a central Vertical section taken through the several tubes of the nozzles, showing diagrammatically the staggering of the air bleed or compensating holes therein and the combined cross-sectional areas thereof.

In the drawings, the numeral 11 indicates a casing, in the side of which is formed an opening 12, forming the air inlet to the carbureting chambers, an opening 13 being provided in the upper face of the casing, constituting the outlet through which the charges, formed in the chambers, pass to the intake-manifold of the engine. The air inlet communicates with a plurality of, in the present case four, Venturi passages, denoted by the numerals 14, 15, 16 and 17, which form independent carbureting chambers, into each of which projects a fuel nozzle 18. These nozzles communicate with a float chamber 19 of any suitable construction, the nozzles associated with the chambers 14 and 17 being controlled, for instance, by needle valves 20. These needle valves control the inlet openings to these nozzles, the inlet openings of the nozzles, associated with the chambers 15 and 16 being fixed, no adjustment being neces sary, as will hereinafter appear. The carbureting chambers 15 and 16 are disposed in the transverse center line of the casing 11, as clearly appears from Figs. 3 and 4 of the drawings, the chamber 14 being located centrally in relation to the chambers 15 and 16, but somewhat in rear of the same, and the chamber 17 similarly in central relation to the chambers 15 and 16, but somewhat in front thereof (Figs. 1, 3 and 4).

Above the carbureting chamber is formed on the casing a horizontally extending hollow cylindrical portion 21, the ends of which are closed by heads 22, on which are formed bearings 23 for the journals 24 of a cylin drical body 25, which is located within and snugly fits the cylindrical portion of the carburetor easing 'lhis cylindrical body 'co'natitiiiiifi a theater valve. will hereinafter appear. The throttle is provided with four bores, denoted by the numerals 26, 27, 28 and 29. The bores 27 and 28 are cylindrical throughout their lengths and extend diametrically through the body of the throttle in the samevdiamet-rical plane, they being adapted to'co-operate with the carbnreting chainbers l5 and 16, respectively. The bores 26 and 29 .intersectone another (Fig. 8), they having separateinlets 30 and 31, respectively, but a common outlet 32. The bores 26 and 29 are disposed between thebores 27 and 28, their inlets co-operating with the carbureting chambers 14 and 17, respectively, and their comm n-outlet with the mixture outlet of the carburetorcasing.

, The casing of the carburetor is so shaped immediately above the cylindrical portion thereof ,that it follows the contours of the discharge ends of ,the bores in the throttle (Figs- .2 nd 3) othat, when the throttle is turned, the discharge ends of the said bores are decreasedcr increased, depending upon the direction. in whichthe throttle is turned. Attention ,is, however, called .to the fact that provision is made in the side of the casing above .'the cylindrical portion thereof that the discharge opening 32 of the bores 26 and 29 is somewhatuncovered when the throttle isdn its fully closed position ('Fig. 5),, so as .to permit ofa flowotair past the fuel nozzle in the chamber 17,,to furnish the propel-amount of combustible mixture for the motor, when running slow without load, for instance when the --automobile, on which the engine is mounted, is at full stop. For turning the throttle, a lever 33 isfixed to oneof its-journals. steps 34 and 35, formed .upon one of the heads 22, limiting the movementof the said throttle.

Each of the carburetor nozzles comprises a tube .36, :the bore of which is divided into a plurality of sections of arying transverse cross-sections. The transverse cross-sections of these bore sections gradually decrease from the uppermost section to the lowermost, as clearly shown in Figs. 1, 2 and 10. The lower end of {the tube is provided with a flange 37, on which rests the flange 38 of a tube 39, which encloses the tube 36 and is spaced therefrom. The upper open end of the tube 39 is disposed a slight distance below the upper end of the-tube 36, onto the latter being titted a cap 40, which extends a substantial distance downwards over the tube 39, but is spaced from the latter. The lower open end of the cap is outside of the suction area of the nozzle, air flowing into the space between the tube 39 and the said cap atsub stantially atmospheric pressure. This air flows into the space between the tubes 36 and 3.9 and from the latter space into the tube 36, as will be presently described. The flanges 37-a11d 38 are disposed in a bore 41 in the carburetor casing, a gasket 42 being interposed between the flange 3S and a shoulder 43 in said bore, the elements being held in proper position by a screw plug 44, having an aperture 45 in constant communication with the float chamber 19. The size of the aperture 45 corresponds", preferably, to that of the lowermost bore section of the tube 36, with which it communicates. The tube 36 is provided with a plurality .of holes 46, one associated with each i-bone section. Through these holes the tube 36 is adapted to communicate with the space between the latter and the tube 39, as will be hereinafter pointed out. Each of the bores 41 is closed by a screw plug 47. Then these plugs and the plugs 44 are removed, each of the nozzles may be removed, as a unit, ,from the carburetor casing. The stems of the needle valves 20 extend through two of .the screw plugs 47.

In Fig. 10 of the drawings the four tubes 36 of the nozzles are illustrated diagrammatically, and from an inspection of this figure ,it appears that not only are the holes 46 in each tube 36 disposed atglifi'erent levels between the fuel inlet to the .tube 36 and'its upper end, but ,the corresponding holes of the several tubes are staggered, that is to say disposed in different planes, the several planes being indicated by lines 48 andthe relative positions of the holes being indicated onthe vertical line 49. The diagram 50 o n the left-hand side of Fig. 10 indicates on each .of the horizontal lines 48 the sum of the transverse cross-sections of the four tubes 36 in lthe plane represented by the said horizontal line. In longitudinal cross-section, therefore, the combination of the four bores oi the tubes 36 give a substantially conical bore, that is to say the transverse cross-section of the bore gradually decreases from its upper end to its lower end.

The operation ofeach individual nozzle of the carburetor is as follows: When the engine is not running, and consequently there is no vacuum in the respective carbureting chamber, the fuel rises in the tube 36 approximately to ,the dotted line shown in Fig. 10 of the drawings and, as the nozzle communicates through the holes 46 with the space between the tube 36 and the tube 39, fuel rises to the same height .in .the said space. From this it appears that the inlet to the nozzle is submerged a substantial distance below the normal fuel level. When the ,engine is started and the .throttle is gradually opened, obviously the suction in the nozzle increases, .thereby lowering the fuel level in the tube 36 and in the space between the latter and the tube 39. The holes 46, which constitute air bleed or compensating holes, are thus progressively uncovered. Since air passes into the space between the cap 40 and the tube 39 at atmospheric pressure and a vacuum exists in the horizontal 9 the tube 36, this air rushes through the said holes into the tube 36 substantially at right angles to the flow of the fuel vapor therein, mixing with the latter and thereby diluting the mixture. The higher the suction acting upon the nozzle, the lower will be the level of the fuel within the same, and therefore more of the compensating holes will be uncovered, permitting of a greater dilution of the mixture. At higher speed the tube 36 is practically empty and all of the compensating holes are in action.

Tests, which have been made with the carburetor herein described, show that the stepped cross-section of the tube 36 gives a material reduction in fuel consumption, and that this reduction in fuel consumption may result from improved atomization of the fuel. It appears that the stepped crosssection gives space for the increased volume due to the mixture of fuel with the air which is vented through the holes 46. Having now reference to Fig. 10 of the drawings, it will be observed that air is bled into the tubes 36 evenly throughout the entire range of the speed of the engine, as said tubes are being emptied. This even feeding of air adds considerably to the cor rectness of the mixture. Moreover, since a combination of the four nozzles results in a conical bore, as indicated by the diagram denoted by the numeral 50, the combined areas of the exposed liquid levels decrease gradually from a maximum to a minimum, so that a gradual dilution of the mixture takes place.

The operation of the carburetor is as follows: When the throttle is in its closed positon, that is to say when it is turned in the direction of the arrow shown in Fig. 1 of the drawings as far as the respective stop will permit, the elements being then in the positions shown in Fig. 5 of the drawings, the carbureting chambers 14, 15 and 16 do not communicate with the carburetor outlet 13. The carbureting chamber 17 communicates, however, through the bore 26 and the common outlet of the last-mentioned bore and the bore 29 with the said carburetor outlet, a minimum opening being provided sufficient to permit of a flow of air past the fuel nozzle in the carbureting chamber 17, thereby furnishing combustible mixture for the motor to permit the same to run idle, that is to say without load. For sometime, during the movement of the throttle toward opening posit-ion, the bore 26 communicates with the carbureting chamber 17 alone, more particularly until the leading edge of the said bore reaches the rear edge of the carbureting chamber 14. The bores 27 and 28 are so positioned in the throttle in relation to the bores 26 and 29 that the carbureting chambers 14, 15 and 16 are cut in simultaneously, more par ticularly when the chamber 17 has reached its maximum capacity. Thereafter the chamber 17 communicates with the throttle passage 29, so that when the throttle is brought to fully open position all of the carbureting chambers are in action.

Inasmuch as the carbureting chambers are not interconnected, obviously the same effect will be obtained as if a plurality of independent carburetors were provided. These carburetors, however, are caused to co-operate, inasmuch as they are controlled by a common throttle. The quantity of combustible mixture drawn may thus be varied in proportion to the desired performance of the engine.

hat I claim is l. A carburetor comprising an air inlet and a combustible mixture outlet, a plu rality of independent carbureting chambers communicating with said inlet, a throttle interposed between said carbureting chambers and said outlet for controlling the communications between said carbureting chambers and said outlet, at suction-controlled nozzle in each carbureting chamber having a bore gradually decreasing in transverse cross-section from its upper end toits lower end, and a fuel connection leading to the lower end of each nozzle, each nozzle being provided with air inlets at different levels between said fuel connection and its upper end, said air inlets being normally sealed at low speeds by the fuel in said nozzles, the air inlets in each nozzle being disposed at different levels than those in the other nozzles.

2. A carburetor including a plurality of independent carbureting chambers, a suction-controlled nozzle in each chamber having a bore divided into a plurality of sections, the transverse cross-sections of said bore sections gradually decreasing in each nozzle from the uppermost section to the lowermost section, and a fuel connection leading to the lower end of each nozzle, each nozzle being provided with air inlets at different levels between said fuel connection and its upper end, said air inlets being normally sealed at low speeds by the fuel in said nozzles, the air inlets in each nozzle being disposed at different levels than those in the other nozzles and the bore sections in each nozzle terminating at different levels than those in the other nozzles.

Signed at New York, in the county of New York and State of New York, this 8th day of May, A. D. 1923.

- JOHN JUHASZ. 

